1. Field of the Invention
The present invention relates to a rectifier for an absorption refrigerator and particularly, to a rectifying apparatus for an absorption refrigerator suited for increasing the performance for regenerating an absorbent solution and a refrigerant liquid.
2. Description of the Related Art
In an absorption refrigerator using absorption refrigeration cycle, a refrigerant which has been vapored and thus lowered in the temperature and an absorbent solution which has absorbed the refrigerant vapor and been high in the temperature are exposed to a chilled water and a cooling water respectively for producing cooling and warming in air conditioning. When the absorbent solution absorbs the refrigerant vapor, it is lowered in the concentration of the absorbent thus decreasing its absorption capability. For recovering the concentration in the absorbent solution, a regenerator in which the refrigerant vapor is released from the absorbent solution is provided. Also, a rectifier is provided for rectifying the refrigerant vapor released in the regenerator to a higher purity level and delivering it to a condenser.
The rectifier is generally a tubular tower called as "a rectifying column" filled with chip type filling materials such as pall rings or Raschig rings. In the rectifier, while the absorbent solution of a lower concentration or diluted solution is passed downwardly through the chip type filling material filler, the refrigerant vapor sent upwardly from the regenerator is forced to directly contact with the diluted solution to increase its purity.
The diluted solution passed downwardly in the rectifier may however run along and close to the inner wall of the rectifier. Also, the refrigerant vapor sent upwardly tends to be lower in the velocity close to the inner wall and higher about the center due to the friction with the surface of the inner wall. Most of the downward flow is pushed by the vapor toward the inner wall surface of the rectifier and this causes less running of the flow about the center. This will discourage the contact between the vapor and the liquid and the purity of the refrigerant vapor will hardly be increased to a desired rate.
For compensation, a modified rectifier using specific filler elements is disclosed in Japanese Utility Model Laid-open Publication No. (Sho) 63-19459. The filler element used here is a tubular form of steel mesh fabricated by rolling a waveform metal fiber such as stainless steel wire. In particular, the roll is characterized in that the concentration of wire is higher in a central region by rolling tight than in an outer edge region. As the filler element is highly intensified in density at the central region, the flow of the refrigerant vapor is biased towards the outer edge where the density is lower and its rising velocity will be uniform throughout the cross section of the rectifier column. The downward flow of the diluted solution passed through the rectifier may tend to run along close to the center of the filler element due to capillary effects. For biasing the downward flow towards the outer edge, a dispersing plate of a conical shape is used together with the filler element.
However, such a conventional rectifier using the above mentioned filler elements offers the following disadvantage. Generally, a plurality of the filler elements are stacked one over another for increasing the purity of the refrigerant vapor. When the filler elements are disposed in layers in the prior art rectifier, the dispersing plates have to be disposed between any two adjacent filler elements as well as at the lowermost of the rectifier. This entails an intricate construction of the rectifier and increases its overall height. Accordingly, the prior art rectifier will be increased in dimensions hence being unfavorable for use in a small, household absorption refrigerator. In addition, the conical shape dispersing plates have to be precisely assembled at given intervals for optimum effect using a complex process in the production.